Hydraulic clutch



Dec. 29, 1925. 1,567,912

R. F. CAREY HYDRAULIC CLUTCH Filed Jan. 16, 1923 6 Sheets-Sheet l Dec29, 1925.

6 Sheets-Sheet 2 R. F. CAREY HYDRAULI C CLUTCH Filed Jan. 16, 1923 1f il'R. F. CAREY HYDRAULIC CLUTCH Dec. l 29, 1925,

6 sheets-s111561' s Filed Jan. 16, 1923 De@ 29l 1925. 1,567,912

\ R. F. CAREY HYDRAULIC CLUTCH Filed Jan. 16, 192,3 6 Sheets-Sheet 4Dee. 29; 1925.

1,567,912 CAREY HYDRAULIC CLUTCH Filed Jan. 16

1923 6` Sheets-Shea?l 5.

Patented Dec. 29, .1925.'

UNITED' sT'ATEs PATENT oFFl'cE.

ROBERT FaLxLAN'n cAnEY, or Laren-oN-sna, ENGLAND.

HYDRAULIC CLUTCH.

Application led January 16, 1923. Serial' No. 612,952. Y i

To all whom t may concern.'

Be it known that I, ROBERT FALKLAND CAREY, a subject of the King ofGreat Britain, residing. at Leigh-on-Sea, Essex,

England, Y have invented certain new and useful Improvements inHydraulic Clutches,

of which the following is a specification.

This invention relates to'that class of apparatus known as hydraulicclutches in which connection between the driving and driven ends of theapparatus is established by locking liquid under pressure in theapparatus and wherein. the release between 'the driving and driven endsis obtained by ,open- 15, ing a passage to allow of free circulation ofthe liquid, and in which variations of speed between zero and maximumcan be obtained by allowing the oil under pressure to circulate to agreater or lesser extent as the fluid passage is morer or lessrestricted at will. -I p i The objects of my invention are to simplifythe construction of such apparatus, thus reducing size and weight andcheapen` r ing cost of production; to obtain, as near as is practical,perfect mechanical balance of parts, which is a most important featurefor high speed running; to so balance' all pres.

sures and thrusts that the bearings are ractically relieved of any loadexcept welg t of the parts themselves, thus eliminatlng wear andallowing of a veryy slmple and cheap l construction of bearing.

Iare to so construct the valve or restricting -device used forcurtailingthe circulation of the liquid that a great {ineness of control of thespeed may be obtained, and to obtaln a solid drive at full speed in aslmple manner, A

A further object is to provide means to allow the clutch power to belimited to a predetermined torque, whether` actlng hydraulically or onthe solid 'dr1ve,. and also to -do away with the use of packmgsaltogether or to so construct the apparatus that the packings can berenewed, without dis- `mantlingthe clutch.

For the purpose of my Ainvention I employ a revolving member 'driven .bythe prime mover or source of powerwhich carries a plurality of radial orapproximately radial cylinders suitable for centrifugal force, eachcontaining a freely reciprocating piston the outward motion of which lisdue to centrifugal force, and ofwhch the inward. mo-

-Further objects tion is imparted by a multistroke cam shapedI trackwhlch surrounds and embraces the `whole of the cylinders and pistons,said track being attached to, or being formed as a part of, a membercapable of rotation attached to the work to be driven. The member ]ustreferred to has attached to it or formed as a part of it a valve orfluid dis- .trlbutlng apparatus in which are formed inlet and outletports, properly positioned 1n relation to the track, tb connect thevarious cylinders to the. inlet or the outlet at theJ proper times, theoutlet port or ports of said valve being connected to a pressurechalnber passage provided Iwith a control valve by means of which 'theflow of the hquld through the passage may be partially restricted oraltogether stopped. The inlet ports are in communication with thecasing.

- A dog or other form of clutching apparatus is also preferably providedto give a solid drive at top speed.

The clutch comprises a driving end and a driven end.

The driving end, which is driven by the S0 prime mover, carries theradial cylinders and pistons. The cylinders are lsually made 1n oneblock called the rotor.

The pistons, which are preferably free, depend for their outwardmovement on cen- 5 trifugal force, the shaped track imparting the inwardmotion. I

The pistons may be ball or roller pistons, themselves revolving aroundthe track or ball or roller headed pistons.

I prefer the ball piston as giving the simplest construction, but ifball or roller headed pistons be used I prefer to form an aperture inthe piston so that the fluid pressure can act directly on the ball orroller.

The driven end is attached to the work and revolves with it and carriesthe multistroke cam shaped track and the valve or 'fluid distributingapparatus and preferably the tracks. have a common feature in ordertoallow centrifugal force to act for imparting the outward movement to thepistons, that is that all bends must be in the same Idirection from thetangent at any point inward towards the centre.

In practice the track will probably always be elliptical, the valvehaving two inlet and two outlet ports.

In my description therefore I confine myself to describing an apparatushaving an elliptical track. All such tracks perfectly balance weightsand pressures and for brevity inA my claims I refer to all such tracksthat I may use in connection with my invention ias cam tracks, the valveinconnection with such having one inlet and one outlet port positionedalternatelyv around the axis for every inward and outward stroke perrevolution imparted to each piston.

My invention will be clearly understood from the following descriptionaided by the annexed drawings, in which :I

Figure 1 is a sectional elevation of the clutch and in which the casingrevolves and wherein the control lis effected by a sleeve which slidesalong the driven shaft over radial openings in said shaft, whichopenings communicate with a passageway extending axially of said shaft.

Figure 2 is a vertical section on the line 2-2 of Figui'e l.

Figure 3 is a vertical section on the line 3-3 of Figure 1.

Figure 4 is a sectional elevation of an embodiment of the clutch whereinthe casing revolves and in which the control is effected by rods whichengage in holes in a disc or wall of the casing.

Figure 5 is a section on the line 5-5 of Figure 4. y

Figure G is a section on the line 6-6 of Figure 4. y

Figure 'l' is a sectionalelevation of an dnibodimcnt of the clutchwherein the casing revolves and in which the casing is only partiallyfilled with liquid, an air space being left or provided to allow forexpansion and contraction of the liquid.

.Figure 8 is a view in elevationtof the einbodiiiient of the clutchshownin Figure 7, showing the lever mechanism for actuating the clutch.

Figure 9 is a longitudinal section of an embodiment of the clutchwherein the casing is fixed and the control is effected in a mannersimilar lto Figure 1, the pistons being shown as roller pistons.

FigurelO is a vertical section on the line 10-10 of Figure 9.

andthe flange 11.

4Figures 11` 12, 13 and 14 are cach a scct'i'on of la rotor andaJ pistonand showing various forms of pistons; and

Figure 15 is a section of a portion lof the casing and disc shown inFigure 1 and showing a spring which serves to press the disc against thecasing.

I will first describe that embodiment of my invention in which the outercasing is attached to the driving shaft of the prime mover and revolveswith it, as shown in Figures 1, 2 and 3.

.Attached to the casing 1, at the end nearest the driving shaft 2, bywebs 1 on the casing 1 is the rotor 3 consisting of a circular blockofmetal having radial apertures 4. say six in number, which act ascylinders and in each aperture 4 is situated a ball 5 having a workingfit in the aperture 4 and acting as a revolving reciprocating piston.The rotor 3 is bored to permit the rotor 3 to run on a central shaft 6which enters said bore and acts as a bearing. This central or drivenshaft 6 acts as the valve or fluid distributing apparatus and its endnearest the driving shaft is at some little distance from the casing 1and the part which enters the i'otor 3 is formed with a pair ofdiametrically opposed pressure or outlet ports 7, 7 which ports 7, 7 areconnected to a central pressure chamber passage S drilled along the axisof the shaft 6 and plugged at the end by the plug 6. The shaft 6 alsohas two inlet ports or slots 9, 9 open to the casing 1 at one of itsends near the driving shaft. These ports 9, 9 are also situateddiametrically opposite each other. Ports 10 ofthe rotor 3, which areconnected with the cylinders 4, .are also connected twice to inlet andtwice to outlet alternately in one revolution of the rotor 3. A'

'lhe shaft 6 is connected to the driven work say by a coupling flange 11and its end extends from the casing 1 through a neck 12 attached theretoand projects beyond same into a non rotating ring piece 12 encirclingrecessed portions iii both the neck 12 Two packings are provided in thering piece 12n between which a groove 11a is situated, such groove 11aconiniunicating with an expansion vessel 35 by a pipe 3G and with theinterior of the casing l by the groove 35. Next to the rotor 3 andsecured to the shaft 6 is a flange or disc 15;

to which is fixed an elliptical track 14 which entirely surrounds andembraces the rotor 3 and the cylinders 4 and pistons 5 of the latter insuch a manner that the pistons 5 roll against the track 14.

Between the flange 13 and the ring piece 12a holes 15 are formed throughthe shaft 6 at right" angles to and communicating with the central holeor passage 8 to which the outlet ports 7, 7 are connected. A collar orsleeve 16 having a' goed fit on the shaft 6 and which revolves with saidshaft but .is capable of sliding on keys 17 on said shaft, serves tocover and uncover the holes 15, 15. This sleeve 16 is actuated by meansof rods 18 passing out of the casing 1 and attached to a circular plate19 surrounding the neck 12, which plate 19 can be moved by a controllinglever or other mechanism in well known manner. The rods 18 are providedwith buttons 21 engaging a groove 22 cut inthe sleeve 16.

This sleeve 16 when moved away from the holes 15, 15 leaves the passagesclear for a free circulation of liquid, the action being as follows.fVVhen the casing 1 and rotor 3 at the driving end are revolved by theprime mover through the shaft 2, the ball pistons 5 move outward undercentrifugal force and press against the elliptical track 14 which, forthe time being, remains stationary, and revolve around it. By reason ofthe shape of the track, the` pistons 5 reciprocate twice in and out oftheir cylinders per revolution of the rotor 3.

As the pistons 5 move outward under centrifugal force, their respectivecylinders are placed in communication with the inlet ports 9, throughwhich fluid flows from the casing 1 into the cylinders, and, when thepistons are being forced inward by the track, are put'into communicationwith outlet ports 7, 7 and through the central passage 8 and rightangled holes 15 back to the' casing 1. In this position of the sleeve 16the liquid (preferably oil) will circulate freely the case 1 and rotor 3revolving with the driving end and the shaft 6, disc 13, track 14,sleeve 16,-and coupling flange 11 i. e. the driven end, remainingstationary.

lVhen the circular plate 19 and the sleeve 16 are moved to cause thesleeve 16 to partially cover the holes 15, 15 the pressure on the oil inthe delivery portion of the sys; tem rises until the pressure is such(because of the restricted orifice and consequent in- -creased liquidspeed with increased inertia and friction) that the resistance of thedriven end is equalled'. After this point is reached anyfurtherrestriction of theholes 15 will cause the driven end to revolve and thegreater the restriction the faster the lform a groove 15b round theshaft 6 where driven end will revolve until, when the sleeve 16 hasentirely closed the holes 15, the driven end will be driven through thelocked oil at a speed nearly equalling that of the driving end but notquite equalling the latter owing to the small loss due to leakage.

Advantage is taken of this small lag to further move the sleeve 16 tocause lugs or teeth 23 formed o n said sleeve to engage lugs or teeth 24formed in a disc 25 which has an angled periphery engagingan angled,ring seating 26 formed in the caslng 1, and

such disc is thus .pressed up. against the seating 26 by sprmgs 27 (F1g.15) positioned in cavities formed by bulbous produe strain may be thrownon the teeth, this P` disc 25 is mounted to slip if the maximum torqueis erceeded. Such disc 25 may be dispensed with and the teeth`24 be madeto engage teeth formed on the casing or other suitable part of therevolving driving end so as to obtain a solid drive at full speed. Thelag makes it possible for the teeth to vcome into engagement withoutundue shock since at that time the two ends are running at nearly thesame speed.- n

An important point in the design of the sleeve or control valve or anyequivalent device used for restricting and shutting olf the liquidpassage is to so design it that, when the restriction Iwas great enoughto cause 90 movement of the driven end, in which event only acomparatively short further movement would be available to give thefurther of speedup to full speed.

l In order to get delicacy and fineness of control over as great a partof the movement of the control lever or other device as possible, it isneccssary-toarrange that, the first part of the movement very rapidlycloses the greater part of the outlet holes 15 and thus leave only avery restricted area available to be further reduced in as gradual amanner as possible with the lever movement available.

In other words, the driven end will not begin to move, if the resistanceisconsidA erable, until the greater part of the area is clbsed and thepressure has increased to the requisite amount to cause movement at all,and the control for giving the different speed :must be effected on theremaining small area, which control should he spread over as much of thestroke ofthe control lever as possible.

One method for accomplishing this is to the right angle holes 15 aredrilled into the central passage, as will he understood from Figure `1,so that the sleeve, instead of cutting ofi' the passageway by simplypass- `restrictions necessary to obtain all variations 9 made anydesired area, areavailable to give the speed control over acomparatively large movement.

According to Figures 4, and 6, instead of the inlet and outlet portsbeing formed in the shaft 6, outlet ports 7 and inlet ports 9 may beformed in the flange or disc 13 to which the track 14 is attached, theflange or disc 13 at the portion having these ports being in the form ofa'liat ring disc or valve kclosable by plugs 3l, and from the chainber Iprovide passageways 15a leading y into the casing 1 and to this casing 1I connect another plate 32 having a neck 12 carrying the plate 19". Inthis case'the plate 19 has two rods 33, 33 which pass through stuffingboxes 34, 34 in the plate 32 and apertures in a bridge extending acrossthe casing 1 through the chamber 30, and then into the passageways 15afor controlling the passage of fluid into and `from the casing 1, andthe ring piece12b instead of carrying the coupling flange 11 and neck12, carries the shaft 1 6 and neck 12. In this case the fluid ypassesfrom the cylinders through the ports 7 and space 13a into the chamberJ30 and out by the passageways 15a, to the casing containing the trackdisc.

The circulation of the liquid should be such as to ensure that the oilmay constantly pass the casing where it is exposed to the air forcooling purposes, and provision should be made for expansion andcontraction of the oil or other liquid used as the clutch medium.

Where a fixed casing is used, all that is necessary for -this latterpurpose is to providey a cup or lexpansion vessel such as 35, as shownin Fig. 1, connected by a pipe 36 to the' casing.

Vhen the casing revolves, a similar cup attached to a ring piecelencircling the end of the casing, which piece does not revolve, willallow the fluid to pass from the cup 35 to the casing inside the plate32, or`vice versa, through the grooves or passages 35a provided for thepurpose and thus allow for expansion.

Another method is to not quite fill the casing with liquid butl to leavean air filled space by which means expansion and contraction are allowedfor.

In the latter case-provision must be made to prevent the air from mixingwith the oil in the circulating system.

This can be done by providing pocket near the centre where the a1r willcollect, the oil being heavier, being driven outwards.

A clutch constructed for this purpose eis shown at Figures 7 and 8.

In this construction the hollow ported end of the shaft 6 shown inFigure l is employed and the circular plate 19a is provided with lugs 23which enter recesses 24 on the outside of the casing 1 in order to give:a solid drive, and such plate 19a carries rods 33 which enter tubes 37having holes 38 communicating with holes 15 of the shaft 6.

The casing 1 is provided with a ring pocket 39 formed in the casing 1 byan angled ring 40 secured to the flange 13c near the centre so as todivert the passage of oil around same and the air will be pocketed nextto the angled ring 40, the oil which is heavier being driven outwards.

In this construction the control is obtained by the rods 33 entering thetubes 37 and gradually covering the holes` 38 and, by the time t heholes 38 have been closed, the teeth 23 have engaged the teeth 24 and asolid drive at full speed is obtained. l

This method is satisfactory only up to certain speeds unless the airpressure in the casing be raised'to suit, since otherwise thecentrlfugal tendency of the oil becomes too great to allow the liquid tofeed the cylinders.

The arrangement shown in Figure 1 is designed primarily for connectionwith a motor lorry and in that case is attached to the fly wheel A onthe driving shaft.

According to Figures 9 and 10 I employ a fixed casing 1d and rollervpistons 5. Otherwise the construction is similar to Figures 1 to 3.

The pistons 5, being roller pistons, re-

quire that the cylinder bore be square or oblong. This is obtained bymaking the rotor in three parts, viz: a central portion, which is milledout vto receive the roller pistons, and two side plates bolted to thecenter portion.

'Ihe shaft4 6 carries the circular plate 19 which is actuated by anarm,20 on a shaft 2Oa journaled in stuffing boxes 20" in the casing 1,and the circular plate 19" also carries rods 33c which enter holes 15bin the disc 132. s

The action is the saine as in Figures 1 and 3 except that oil is alsoadmitted to the ports 92, 92 on both sides of the rotor, instead of onplate 19b so that the two revolve together.

Figures 11, 12, 13 and 14 show various types of pistons.

F 1g. 11 shows a solid ball piston 5 coni ciated with sai llic nected toand retained by alsolid block or plunger A slidin in the cylinder 4, theubrication being rom the casing, the pressure acting on the plunger A.

Fig. 12 shows a roller piston 52 pivoted to a bifurcated end of a solidblock or plunger A2 sliding in the cylinder.

Fig. 13 shows a solid ball piston 53 connected to and retained by atubular block A, the pressure in the` cylinder acting on the ball.

Fig. '14 shows a 'hollow roller piston 54 connected to and retained by atubular plunger or block A4 for pressure in cylinder to act on rollerA54. v

Fig'. l5 is a detail view of the mou'ntings for the springs for drawingthe angled ring shown in Fig. 1 to its seat.

What I do claim as my invention and desire to secure by Letters Patentis 1. A hydraulic clutch comprising a fluidcontaining casing, a pressurechamber associated with said casing and normally in communication withthe latter, a driving member, a driven member, a cam track within saidcasing and connected to said driven member, a rotor within said casingconnected to said driving member, said rotor having a plurality ofradially arranged open-ended cylinders and a plurality of -passagewayseach leading to the inner end of one of said cylinders, a piston Workingin each of said cylinders and adapted to pro--l ject from the outer endof the latter into engagement with said cam track, means for bringingeach of the passageways of said cylinders alternately into communicationwith said fluid-containing casing and with said pressure chamber, andmeans for throttling the flow of fluid from said pressure` chamber tosaid Huid-containing casing and maintaining pressure behind said pistonsto cause the latter to clutch said cam track.

2. A hydraulic clutch comprising a fluidcontaining casin a pressurechamber assocasing and normally in communication with the latter, adriving member, a driven member, a cam track within said casing andconnected to said driven member, a rotor within said casing connectedtosaid driving member, lsaid rotor having. a plurality of radiallyarranged open-ended cylinders and a plurality of passageways eachleading to the inner end of one of said cylinders, a plurality ofpistons each working in one of said cylinders and adapted to projectfrom the outer end of v the latter into engagement with said cam track,means for bringing each of the passageways of said cylinders alternatelyinto communication with said fluid-containingy casing and with saidpressure chamber, and

means operable during'a part of its move- 'ally extending open-ende mentto throttle communication between said pressure chamber and saidfluid-containing casing to maintain pressure behind said pistons and tocause same to clutch said cam track, said means operable during itsfurther movement to connect said driving member directly to said drivenmember.

3. A hydraulic clutch comprising a fluidcontaining casing, a pressurechamber associated with said casing and normally in communication withthe latter, a driving member, a driven member, a cam track within saidcasing and connected to said driven member, a rotor within said casingconnected to said driving` member, said rotorhaving a plurality ofradially arranged open-ended cylinders and a plurality of passagewayseach leading to the inner end of one of said cylinders, a plurality ofpistons each Working in one of said cylinders and adapted to projectfrom the outer end of the latter into engagement with said cam track,valve means associated with said driven member and operable toalternately permit the flow of liquid fromsaid. fluid-containing casingthrough said passageways of said cylinders and from said cylinders tosaid pressure chamber, andl means for throttling communication betweensaid pressure chamber and said fluid containing casing.

4. A hydraulic clutch comprising a fluidcontaining'casing, a pressurechamber associated with said casing and normally in communication withthe latter; a driving member; a driven shaft having bearing in saidcasing; a cam track within said casing and connected to said drivenshaft.; a rotor- Within said casing connected to said Y driving memberand rotatable on said driven shaft; said rotor having a plurality ofradicylinders and also having a plurality of passageways, one for eachcylinder, leading to said cylinders adjacent the inner ends of thelatter; a plurality of pistons, one working in each of saidy c lindersand projecting from the outer en of' the latter into engagement withsaid cam track; valve means associated with said driven shaft andadapted `upon the rotationof said rotor to alternately bringreach of thepassageways of said cylinders into communication with said casing andwith said lpressure chamber, and means for controlling communicationbetween said pressure chamber and said cas-A In testimony whereof I havehereunto set my hand.

ROBERT FALKLAND CAREY.J

